diff --git a/CHANGELOG.md b/CHANGELOG.md
index a3d74544..238c23a9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@ Version 81:
 * Pass string_view by value
 * better is_final on empty_base_optimization
 * Suppress incorrect GCC warning
+* multi_buffer ctor is explicit
 
 --------------------------------------------------------------------------------
 
diff --git a/include/beast/core/multi_buffer.hpp b/include/beast/core/multi_buffer.hpp
index 4b961756..05a0279b 100644
--- a/include/beast/core/multi_buffer.hpp
+++ b/include/beast/core/multi_buffer.hpp
@@ -116,6 +116,7 @@ public:
 
         @param alloc The allocator to use.
     */
+    explicit
     basic_multi_buffer(Allocator const& alloc);
 
     /** Constructor.